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Chris Boshoff, Senior Vice President of Immuno-Oncology, Translational and Early Development at Pfizer, and colleagues Samra Turajlic and Charles Swanton from the Francis Crick Institute and University College London give us their personal point of view on new insights and future therapeutic approaches for renal cancer.

Most practicing physicians will recall from their training that the average prognosis for patients with central nervous system (CNS) metastases from melanoma was death within a matter of weeks to m...

Immune-checkpoint inhibitors (ICPIs), including antibodies against cytotoxic T-lymphocyte associated antigen 4 and programmed cell death protein 1, have been shown to induce durable complete responses in a proportion of patients in the first-line and refractory setting in advanced melanoma and renal cell carcinoma. In fact, there are several lines of both targeted agents and ICPI that are now feasible treatment options. However, survival in the metastatic setting continues to be poor and there remains a need for improved therapeutic approaches. In order to enhance patient selection for the most appropriate next line of therapy, better predictive biomarkers of responsiveness will need to be developed in tandem with technologies to identify mechanisms of ICPI resistance. Adaptive, biomarker-driven trials will drive this evolution. The combination of ICPI with specific chemotherapies, targeted therapies and other immuno-oncology (IO) drugs in order to circumvent ICPI resistance and enhance efficacy is discussed. Recent data support the role for both targeted therapies and ICPI in the adjuvant setting of melanoma and targeted therapies in the adjuvant setting for renal cell carcinoma, which may influence the consideration of treatment on subsequent relapse. Approaches to select the optimal treatment sequences for these patients will need to be refined.

Introduction Immune Checkpoint inhibitors (ICPi) have revolutionised the management of melanoma, non-small cell lung cancer and renal cancer. They block receptors expressed by immune cells that reduce immune activation. ‘Turbo-charged’ immune cells deliver augmented anti-tumour immunity (hence the striking efficacy of these anti-cancer agents), but comes at the cost of immune mediated side effects. Immune-mediated damage to the gut is a common and serious side effect of ICPi therapy. Endoscopic and histological findings in the lower gastrointestinal (GI) tract have been described (colitis is a common feature), but little is known about manifestations in the upper GI tract. Methods We performed a retrospective analysis of all patients presenting with diarrhoea following treatment with ICPis (ipilimumab, nivolumab, pembrolizumab or combination therapy) who had been investigated with OGD. Endoscopic and histopathological data were recorded. Lower GI findings in this cohort were also analysed. Results We reviewed 40 OGDs performed in our unit for melanoma patients who developed diarrhoea after starting treatment with ICPi patients. In all cases flexible sigmoidoscopy or colonoscopy was also performed. Inflammatory changes were common, including gastritis (40%) and duodenitis (17.5%). Importantly, even in the absence of macroscopically visible mucosal injury, there was a significant burden of microscopic inflammation, especially in the duodenum. In patients with a normal duodenoscopy, significant microscopic changes were present in 28% of patients. Significant histological abnormalities included chronic inflammation and/or increased intraepithelial lymphocytes (86%) and villous atrophy (71%), consistent with pathologically relevant mucosal immune activation. Abnormalities in the oesophagus were also common (32%), but were dominated by candidiasis (15%), likely secondary to high-dose steroids used to treat this challenging condition. All patients in this cohort of ICPi-induced diarrhoea patients investigated with OGD additionally underwent lower GI endoscopy, which confirmed the presence of colitis in 65% of patients. Importantly, upper GI disease was just as common in patients with a normal lower GI investigation (57%) as those with overt colitis (54%). Conclusions There is a significant burden of upper GI pathology, including macroscopic and microscopic mucosal injury and excessive immune accumulation, most notably in the duodenum, in patients with diarrhoea secondary to ICPi therapy. Additional findings that altered management included oesophageal candidiasis (likely a side-effect steroid therapy, which is usually rapidly initiated as soon as patients present with diarrhoea). Importantly, upper GI pathology is just as common in patients without colonic disease. OGD should be part of diagnostic work up of patients developing diarrhoea in the context of ICPi therapy.

Introduction Immune checkpoint inhibitors (ICIs) such as ipilimumab (ipi), nivolumab (nivo) and pembrolizumab (pembro) and the combination of ipi +nivo have improved response rates and survival in patients (pts) with advanced melanoma. Nivo was recently approved by the FDA as an adjuvant therapy. Responses may be durable, however associated immune-related adverse events may result in significant morbidity. Current treatment algorithms suggest that pts treated with ICIs who develop corticosteroid (CS)-refractory (CSrefr) irD/C are prescribed anti-TNF alpha antibodies such as infliximab (IFX). Little is known about the clinical features and outcomes of pts who receive IFX. Methods Pts with advanced melanoma from the Royal Marsden NHS Foundation Trust who received CS and IFX were identified from an ethically approved irD/C database (pts treated with ICIs from 2011–2016) and their medical records were reviewed, including flexible sigmoidoscopy (FS) results. Descriptive statistics and percentages were used to summarise the features of the CSrefr versus CS-responsive (CSresp) groups. Results Rates of all-grade irD/C by course of treatment were as follows: ipi 77/285 (27%), nivo or pembro 17/166 (10%), ipi +nivo 23/68 (34%). CS were prescribed in 72 (62%). 17 (15%) received IFX; 9 received 2 doses and 3 received 3 doses. 76% responded to IFX within a week; median time to improvement was 4 days (range 1–28). Table 1 outlines clinical information for the CSrefr and CSresp groups. Infection occurred in 10 episodes of IFX prescription (59%), 9 requiring antibiotics, including 2 cases of Pneumocystic jirovecii pneumonia. Conclusions 35% of irD/C due to ipi +nivo is CS-refractory. In the CSrefr group, CS duration was longer, macroscopic colitis was more common and most pts developed an infection. Interestingly time to progression of disease was longer in the CSrefr group. Prospective clinical trials are warranted to evaluate whether early IFX may reduce the burden of CS in the management of irD/C without compromising disease control.Abstract PTU-005 Table 1 CS-refractory versus CS-responsive patients CSrefr (n= 17) CSresp (n= 54) N (range) % N (range) % Ipi 8 47 30 56 Nivo/pembro 1 6 9 16 Ipi+nivo 8 47 11 20 Days from start ICI to onset of irD/C 41 - 45 - Grade 1/2 1 6 14 26 Grade 3/4 16 94 40 74 Median days from start of D/C to CS (range) 5 - 5 - Days from start CS to IFX 14(1–100) - NA - Median duration CS - - Grade 1/2 160(160–160) - 49(6–295) - Grade 3/4 79(28–279) - 47(6–204) - Extra treatment 1(vedolizumab) 6 0 0 Macroscopic abnormality on FS 13/17 76 22/41 54 Microscopic abnormality only on FS 1/17 6 9/41 22 Normal FS 2/17 12 7/41 17 Unknown FS result 1/17 6 3/41 7 Disease progression 12 67 42 79 Median days to progressive disease 170 - 101 - NB: 1 patient who had CS but unknown status re IFX is not included

Background Immune checkpoint inhibitors (ICIs) including anti-CLTA-4 (e.g. ipilimumab (ipi)) and anti-PD-1 antibodies (e.g. nivolumab (nivo)) have improved outcomes in many cancers. However their use is complicated by ICI-related diarrhoea/colitis (irD/C), a common cause of morbidity and ICI discontinuation. The National Cancer Institute’s Common Terminology Criteria for Adverse Events (CTCAE) has been used to grade irD/C according to frequency of bowel movements over baseline. Grade 1–2 represents mild-moderate disease, grade 3–4 severe disease and grade 5 represents death. In clinical trials diarrhoea/colitis is more common in regimes using anti-CTLA-4 agents.1 There are few real world data reported in the UK. Methods Electronic medical records were reviewed for melanoma patients (pts) at The Royal Marsden Hospital (RMH) and melanoma, renal and lung cancer pts Guy’s and St Thomas’ Hospital (GSTT), receiving at least one ICI dose between 2011–2016. Clinical outcome data included class of ICI therapy and CTCAE grade of diarrhoea. Results 651 ICI treatment courses were administered mostly for melanoma (100% RMH, 53% GSTT). 285 (44%) received anti-CTLA-4 monotherapy, 288 (44%) anti-PD-1 monotherapy, and 77 (12%) combination ipi +nivo. The incidence of all-grade irD/C was 27% for anti-CTLA-4 therapy, 12% for anti-PD-1%–34% for ipi +nivo. The incidence of severe irD/C (grade 3–5) was 12% in anti-CTLA-4 monotherapy, 4% in anti-PD-1 therapy and 26% in combination therapy (figure 1). There was one only death reported in a pt who developed colitis following treatment with anti-CTLA-4 monotherapy.Abstract PTU-006 Figure 1 Conclusion This is the largest cohort of data reporting the incidence of irD/C involving real-world patients. Compared to trial data, the incidence of all-grade diarrhoea was slightly lower but the incidence of severe disease was higher in all treatment groups, particularly with ipi +nivo. Given the expansion of ICIs in other cancer types and use as an adjuvant therapy, there is an urgent need to engage gastroenterology services and to develop evidence-based management algorithms for treatment of irD/C. Reference . Spain L, Diem S, Larkin J. Management of toxicities of immune checkpoint inhibitors. Cancer Treat Rev2016;44:51–60.

Background Immune check point inhibitors (ICPis) have transformed the treatment landscape for several cancers, but at the cost of triggering ICPi-induced colitis which resembles some aspects of IBD. Diagnosis is often made by symptoms, or by identifying endoscopic features of colitis. Little is known about histological findings in the absence of macroscopic disease. Furthermore, first-line management strategies beyond the use of systemic corticosteroids have not been explored. Our aim was to assess the incidence of microscopic inflammation in patients with ICPi-diarrhoea, and report our experience of treating two such patients with beclomethasone diproprionate (Clipper). Methods Electronic records of patients with advanced melanoma and ICPi- diarrhoea/colitis at the Royal Marsden Hospital (RMH) and Guy’s and St Thomas’ Hospital (GSTT) between 2011–2016, were retrospectively reviewed. Endoscopic, histological and clinical outcome data was recorded for patients who underwent flexible sigmoidoscopy and had colonic biopsies taken regardless of macroscopic findings. Two symptomatic patients (one treated with anti-PD-1, and another on combination -anti-PD-1/anti-CTLA-4 therapy) with isolated microscopic disease were managed with 5 mg Clipper, once a day, for 4 weeks. Endoscopic, histological and clinical outcomes were recorded 6 weeks after completion of therapy. Results A total of 63 flexible sigmoidoscopies were performed in 59 patients with ICPi diarrhoea/colitis. Microscopic inflammation with normal macroscopic appearances were recorded in 22% of cases. 6 patients were prescribed anti-CTLA-4, 4 anti-PD-1, and 4 combination therapy. Histological features that were distinct from conventional microscopic colitis were recorded in the majority of patients (10/14), which included acute and chronic inflammation, architectural distortion, crypt abscess formation and neutrophil infiltration. Four patients had changes consistent with conventional microscopic colitis (2 lymphocytic colitis, 2 collagenous colitis). Clipper induced clinical remission within 7 days, and histological remission by week 6 in both patients with ICPi-induced microscopic inflammation. There was no treatment associated adverse events. Conclusion Microscopic inflammation in the absence of macroscopic features of colitis is a common finding in ICPi-induced diarrhoea, justifying the routine practice of performing colonic biopsies even when endoscopy is normal. Our favourable clinical experience of using Clipper in 2 patients with microscopic inflammation merit further investigation in appropriately controlled clinical trials.